Without looking up any leaks or rumors, I’d bet that you could probably sketch most of the phones rumored to be launching at Mobile World Congress next week. Over the years, smartphones have settled on a relatively consistent design formula of big rectangular touchscreens, small selfie camera cutouts, app-based interfaces, and large camera bumps with an array of different lenses. But more than a decade and a half into the smartphone era, I’m getting more and more curious about what’s going to co...